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    <a href="../index.html">cppreference.com</a> &gt; <a href=
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    clear
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    Syntax:
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  <pre class="syntax-box">
  #include &lt;fstream&gt;
  void clear( iostate flags = ios::goodbit );
</pre>

  <p>The function clear() does two things:</p>

  <ul>
    <li>it clears all <a href="../io_flags.html#state_flags">io stream
    state flag</a>s associated with the current stream,</li>

    <li>and sets the flags denoted by <em>flags</em></li>
  </ul>

  <p>The <em>flags</em> argument defaults to ios::goodbit, which means
  that by default, all flags will be cleared and ios::goodbit will be
  set.</p>

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    Example code:
  </div>

  <div class="related-examples">
    <p>For example, the following code uses the clear() function to
    reset the flags of an output file stream, after an attempt is made
    to read from that output stream:</p>
    <pre class="example-code">
 fstream outputFile( &quot;output.txt&quot;, fstream::out );            

 // try to read from the output stream; this shouldn&#39;t work
 int val;
 outputFile &gt;&gt; val;
 if( outputFile.fail() ) {
   cout &lt;&lt; &quot;Error reading from the output stream&quot; &lt;&lt; endl;
   // reset the flags associated with the stream
   outputFile.clear();
 }              
                

 for( int i = 0; i &lt; 10; i++ ) {
   outputFile &lt;&lt; i &lt;&lt; &quot; &quot;;
 }
 outputFile &lt;&lt; endl;              
</pre>
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    Related topics:
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    <a href="eof.html">eof</a><br>
    <a href="fail.html">fail</a><br>
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